iOS 7 Programming Cookbook

20.2. Drawing Text

Problem

You want to be able to draw text on the screen of an iOS device.

Solution

Use the drawAtPoint:withFont: method of NSString.

Discussion

To draw text, we can use some really handy methods built into the NSString class, such as drawAtPoint:withAttributes:. Before we proceed further, make sure that you have followed the instructions in this chapter’s Introduction. You should now have a view object, subclassed from UIView, named View. Open that file. If the drawRect: instance method of the view object is commented out, remove the comments until you have that method in your view object:

#import "View.h"

@implementation View

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
    }
    return self;
}

- (void)drawRect:(CGRect)rect{

}

@end

The drawRect: method is where we’ll do the drawing, as mentioned before. Here we can start loading the font, and then draw a simple string on the screen at point 40 on the x-axis and 180 on the y-axis (Figure 20-6):

- (void)drawRect:(CGRect)rect{

    UIFont *helveticaBold =  [UIFont fontWithName:@"HelveticaNeue-Bold"
                                             size:40.0f];

    NSString *myString = @"Some String";

    [myString drawAtPoint:CGPointMake(40, 180)
           withAttributes:@{
                            NSFontAttributeName : helveticaBold
                            }];

}

In this code, we are simply loading a bold Helvetica font at size 40, and using it to draw the text Some String at point (40, 180).

Figure 20-6. A random string drawn on the graphical context of a view